police are looking into a mysterious death, a witness in a high profile mob trial found dead, the latest twist in the trial of james whitey bulger, one of the nation's most nor tore yus crime suspects. Ron claiborne has the story. Reporter: He was a courthouse regular. Coming each day to the whitey bulger trial. Waiting for the day when he would testify against the reputed longtime head of the boston mob. Bullet piercing eyes. There's no heart. He probably sleeps in an ice chest. Reporter: That was stephen "slippo" rakes just a few days ago. He was really anxious to testify. Reporter: Rakes would never get that chance. On tuesday, he was dropped from the witness list. The next day, he wasn't at court. And today, a dead body found on the side of the road in a wealthy boston suburb was identified at rakes's. The man he was so anxious to testify against, bulger, was in court today. Listening as his alleged former partner in crime, stephen, the rifleman, flemmi, took the stand for the prosecution. He was asked what was your relationship to bulger. Strictly criminal. Bulger an trial, a witness dead, a mistress unsolved. Ron claiborne, abc news, boston.

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